As for lighting... the bottle battery systems work pretty well and it is hard to beat 20 to 30 watts of light on a bike.
I use a Niterider system and am quite pleased with the quality of light (the price was outragous however). I also back up my great system with a good system of battery powered lights and flashers. And I back that up with a cheezy little generator system. One way or another, I will have lights when I commute.
I have yet to get the Airzound, but I have heard it and it is on my list. As far as peds and MUPs go, I talk to the peds and tell them I am coming, and thank them for moving and wish them good days and all kinds of positive stuff like that... seems to work just fine.